Hoisting apparatus



Oct. 27, 1931. c pFATT 1,828,748

HOISTING APPARATUS Fileg July 26,1928 5 Sheets-Sheet 1 A TTORNEYS.

Oct. 27, 1931.. c, R PRATT 1,828,748

I HOISTING APPARATUS Filed July 26. 1928 @3];Sheets- Sheet 2 IN VEN TOR.

A TTORNEYS.

rp a te ntdloct. 27,1931 j 'foneiinns:

invention? relates toa'n improvement in hoisting machines tind -is p2irticularlyadapted for elevator service; One of the obj ect's of myinvention istlie provision of a" hoisting maohineof ne'wfand novel-construction which "is inherently relatively free vofVibration and 'sr'noothliii operation.

'A-j'further' ob'ect ofiny invention is the pro+ vision of hoisting" machine employing 9,

o multi-motor drive which by compaotdesign is 'considejrably smaller than al gearless or a r hence: satisfactory operation obtained as distinguished from aworinge ztr drive ernploy-' ing several motors in 'Whicheflectiife' reaction -b'etivee'n the rnotors is resisted by thejlockingf Worm gear hoisting-machine vfor the" same :Serv1ce. l 1

More specifically the present inyentionf 'nfovide's" ii hoisting mzi'chine which is capable "vi ithesise ofai- 'car speed'frOInEtWO hundred to twelve hun'dred..feet"1per minutes This is" a "decidedfajdvanceover Worm-gearelevator chines; th ese machines being unsu ted ",f'or

,1 go-j speeds; 'oyer threehundred ffeet pefr 'minute.

iniprovedniach'ine is superiorjtothi gears T less maohines which are hot 'a' laptedjf r speeds jbelowf siX hundred' 'feet per minute. 7 InotherWords-in the hoisting'niaeh'ine art tov H- flay therefis 'zi speedhietu's between-three hundred and "six hundred "ifeetiper m yute Which is b i g by my invention," A 'sti'll fu therob'e'ct "of myinvention is the provision of a spur gear" driven hoisting ma chinef which; as mentioned above will'be releltiV-elyfree'of vibration and i'n Whichfthe driye'is s'ofarrenged ads-to prevent detrimental toothstminsw I Q 9 A further object ofthe present invention :3 isthe provision of a hoisting machine equipped Wither brake pulley .which is provided with internal teeth so that this pulley;

not only functi'ons as s; brake pulley but as an internal spur gear to which the traction .1140 sheave is directly attached;

. V "More sp cificall the present invention vides a? hoisting machine of high efliciency "which particularly well adapted for use} 1 elevator installations inw'hich', an internal o 2 45 spur gear,as'mentionedabove carried bythe With the internal; s p'ufge'a r giving "a smooth,

"brake-5 pulley and diree'tly: attached to "the etr'action sheave,jis}driven' by 'a; "plurality of 'elecitricjniotor'sf each 'niotor being' pr'oyided with a "spur *gearpini on in staggered mesh meme sthmusered;

mesh with-the internal gear; 1

spur gear and spur gear pinions reflective reaction between the motors isperm1tted' and action of the s'everal motors vdriving. one Worn; g'e'al'r w'lileh' Causes initial tooth strain asWellas'interrupted' notion ofthe elevator I t:

' Y My invention ByeinpIOyingeJ plurality of "motors ea'ch' a; spur gear piniondneshing with an'finternaljspur ear marasaarurms ia-dventagees eo npa'red'with slovi speed gear-s 'jle'ss motors-iin the tfthe severel "high speed f' 'mot'ors employed by me eigh and cost less I Y H jthen a single"slow speed gearlessmotonof" 5 a horse power equgl tdtlfe *coinhined h'oi'sepower of the several high speed motors, No extra; space "is required in installing inyi1 1 'vention, the severel hi'gli'f'speed" 'inotors em plo'yed together with, the" internal spur ge :occupying only: the space; now oeeupied thelwormgearcase onawormfgeer machine l e -for equal dutyi l 1 mThe machine of th is invention is -alsocon' flstrueted sot-hat; the plurality of motors em- 7 eployed for clrivin'g-ere held between two steel plates, Qohtaining in parallel alignment of "the 1; l armature shafts of the;motors and-rperfeet m eshc of theirrespective pinions with the l nt rnal d iven 'sPe e ar; J

In the aceor npanying' drawings, Figsl is a; part sectional side elevational Embodiment of niyjinvention F g" 2's a nd. vi wp n ysinf silent and'durable transmission then two teethoflach piniofifbeingjzit all p 1 view, of, a

nfbeingteken 1 Fig. 4 is an enlarged view of one of the spur gear pinions employed together with the internal driven spur gear.

1 designates a traction cable sheave shown in section on Fig. 1, this traction sheave being rigidly attached as by bolts 2 to a brake pulley 3 c-provided .on the inside with spur gearlteethq- The traction sheave 1 ismounted on a shaft 4: which is supported for rotation 1n a'bearlng 5 at one end a'ndia bearingl6 at theother end. This latter bearing is provided in plates to be hereinafter referred to by which the several motors employedfor driving the,internal spur gear' or brake drum are" 1;} As above ointed outmy improved machine comprises a plurality of electric motors, two

or more, for driving the internal spur gear 3.

I ,mays'ay at thispoint thatthe member 3 will be hereinafter referred to as an internal spurgear, it being borne in mind that I make use of, in the present instance, the brake drum as this gear. By Way of illustration four motors designated7, 8, 9 and 10, respectively, have been shown for driving the internal spur gear 3, these motorsbeing pro- ,vided with spur gearpinions 11, 12, 13 and 14, respectively.

Asabove pointed out a construction is provided for insuring perfect alignment of the armature shafts of these motors and perfect -mesh 'between the teeth of the several pinions 11, 12,13 and l t andjthe internal spur gear 3, I have, therefore, provided two plates .15;an d 161 bored for the reception of the'fdriving motors, eachmotor having its louterlbodyg or frame turned-concentric with es imates; shaft with" shoulders at each I Theseshoulders abut the-plates 15 and 1 6 and bolts 17 clamp the structure together --into a unitary'structure,the motors being ,heldin perfect alignment thereby. The shaft 4 hereinbefore mentioned is also received by the two plates l and 16 which provide a bear ng therefor sothatthe entire structure including the motors, internal spur gear 3,

etc. are held in perfect axial alignment to give the desired alignment and mesh between the teeth of the pinions 11, 12, 13 and 14c and the teeth of the internal spur gear 3. To further insure this desired construction the ,plates 15 and 16 are bored originally while bolted together. so that their bores are necessarilyexactly alike.

" 1 The teeth of the pinions are in staggered mesh with the teeth of the internal spur gear 3 and as mentioned above not less than two teeth of' each'pinion are always in mesh with the gear have attempted to illustrate "this {inF 4, an inspection of which figure "will" show that theteeth 18 and 19 are in mesh ,vvith the teeth of the internal spur gear. In actual practice to obtainthe staggered mesh desired and not less than two teeth of each pinion in constant mesh with the internal gear 3 I employ for example four pinions, each having fifteen teeth wlth a p1tch diameter of three and three-quarter inches while the internal spur gear may have a'pitch diameter of thirty-seven and one-quarter inches and be provlded with one hundred forty-nine teeth. This gives me a constructionin which the driving torque of four motors is applied direct to the traction cables dividing the total load equally between the fourmotor. pinions, whereby the cables are driven. by from eight to twelve pinion teeth and solid steel pinions which are practlcally silent may be used, although if desired lam- .inatedsteelor ,non-metalliepinions can be used-for greater silence. Also by this arrangement' one too-thof one pinion is at all times in perfect mesh with anlnternal gear tooth, the teeth in the other three pinions successfully approaching this perfect mesh thereby substantially eliminating vibration,

noise and wear inherent in any single pinion dTlVB. mach ne.

It will be apparent also to those skilled in this art that my invention provides for desirable reaction between the several driving ,motors.

Itv will be seen from. the foregoing, therefore, that I have provideda hoisting machine employinga plurality of driving motors, in the. present instance four, each motor being provided with a pinion and these p nions being arranged in staggered mesh with alarge internal spur gear which is formed on the brake drum.

Obviouslychanges may be made inthe details of construction above described and in.

the controller arrangement within the purviewof my invention.

1. A hoisting machinedcomprisinga traction sheave, a gear secured thereto, .a shaft for mounting the traction sheave, apair of ,tion sheave, an internal spur gear, secured thereto, a shaft for mounting the traction sheave, a pair of platesproviding abe'aring for sald shaft, aplurality of electric ,motors having their housings mounted directly in said-platesand clamped thereby, to provide a unitary structure. for holding the motors rigidly in symmetrical relation to the sheave shaft, and a pinion mounted on and driven bythe armature shaftof each, motor, said rsaprspinions being in staggered mesh with said 3 gear. l a p 3 1 3. hoisting machine comprising in combinatlon a traction sheave, an internal gear '1 for driving the same,'a shaft carrying said sheave, a pair of plates providing a bearing for said shaft, aplurality of electric motors 7 having their housings mounted directly in and supported directly'by said plates, a pin- 1' ion on the armature shaft of-each motor, said pinions meshing with said internal gear.

4. A hoisting machine comprising in combination a spur gear, a plurality-0f electric motors, a pinion attached to the armature 15 shaft of each motor andmeshing with said spur gear, the outer surface of the field structure of each motor being formed concentric with its armature shaft and provided with spaced shoulders, plates'bored to fit the field 2o structures and rigidly engaging the shoulders on the field structures rigidly to support 7' the motors, a shaft carrying said spur gear, said shaft having a bearing in said plates 10- cated centrally with respect to the bores for 25 the motors, whereby all of said pinions are i held in precise axial alignment and in accurate radial mesh with the spur gear. 7 This specification signed this 24th day of July, 1928; V 1 so CHARLES R. PRATT. 

